1. Field
This application relates generally to wireless communications, and more particularly to handling handovers during a wireless communication session.
2. Background
In contrast with other handover mechanisms, such as those used by WCDMA R99, HSPDA and other similar technologies allow for only a single radio link (one sector) for downlink data transmission. This serving sector or cell, which transmits HSDPA to data to the mobile handset is referred to as the HS serving cell. The HS serving cell needs to be tracked by both the network and the mobile handset. Typically, the method to do so is through event 1d (e1d) reporting.
When the mobile equipment establishes an HS call, the sector or cell that sets up the call will become the first “Best Cell”, and it will be reported to the mobile handset through an e1d measurement report message (MRM). When the mobile handset moves to another cell or sector, soft handover occurs and the mobile will add the new cell into its Active Set. The mobile handset will compare both cells in terms of strength and then report to the network if the new cell is stronger through an e1d MRM. The network may then send a reconfiguration message to change the HS serving cell to the new cell.
In conventional e1d handling, when an active set cell other than the best cell satisfies an e1d triggering condition, a timer is started for that cell. If the condition has been satisfied for a time period longer than the timer, the handset then set this cell as the best cell and sends an e1d measurement report. All timers are then reset. There may be other fast rising pilots that are becoming even stronger than this new best cell before the expiry of its timer. However, in the conventional handling, there is no mechanism to record when the new fast rising pilot becomes stronger than the new best cell. Accordingly, the strongest new fast rising pilot will have to wait another timer period to be reported.
It would be desirable to have a system and method for tracking such fast rising pilots.